<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <style>
    #box div{
      width: 100px;
      height: 100px;
      background: red;
      border-radius: 50%;
      position: absolute;
      left: 0;
    }
    #ball1{
      top:0
    }
    #ball2{
      top:110px
    }
    #ball3{
      top:220px
    }
  </style>
</head>
<body>
  <div id="box">
    <div id="ball1"></div>
    <div id="ball2"></div>
    <div id="ball3"></div>
  </div>
</body>
<script src="index.js"></script>
</html>